Alert archive / Oklahoma / Mesoscale Discussions in 2014

Mesoscale Discussion 511

May 7, 201411 counties in Kansas; 16 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at May 7, 2014, 4:41 PM CDT for 11 counties in Kansas; 16 counties in Oklahoma. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
May 7, 2014, 4:41 PM CDT (21:41 UTC)
Expired
May 7, 2014, 5:45 PM CDT
In force
64 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 27 counties

Barber County, KS, Butler County, KS, Chase County, KS, Harper County, KS, Harvey County, KS, Kingman County, KS, Marion County, KS, McPherson County, KS, Reno County, KS, Sedgwick County, KS, Sumner County, KS, Alfalfa County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Grant County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Major County, OK, Noble County, OK, Washita County, OK, Woods County, OK

The radar

The Vance AFB radar (KVNX), 19 km from the middle of the area, began a volume at 21:41 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 9.7 hours before the alert went out and 163 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2014-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 605 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2014-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 421 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
605 J/kg
Mixed-layer CIN
-552 J/kg
Mixed-layer LCL
1267 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
421 m²/s²
0-3 km storm-relative helicity
395 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

297 
ACUS11 KWNS 072141
SWOMCD
SPC MCD 072141 
KSZ000-OKZ000-072245-

MESOSCALE DISCUSSION 0511
NWS STORM PREDICTION CENTER NORMAN OK
0441 PM CDT WED MAY 07 2014

AREAS AFFECTED...NRN AND CNTRL OK...SCNTRL KS

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 123...

VALID 072141Z - 072245Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...AN ISOLATED SEVERE THREAT MAY DEVELOP OVER THE NEXT FEW
HOURS ACROSS NRN OK AND SCNTRL KS. LARGE HAIL AND WIND DAMAGE WILL
BE THE PRIMARY THREATS WITH THE ACTIVITY. AN EXTENSION OF WW 123 TO
INCLUDE PARTS OF NW OK MAY BE NEEDED. IN ADDITION...WW ISSUANCE MAY
BECOME NECESSARY TO THE NORTH OF WW 123 ACROSS PARTS OF SCNTRL KS.

DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A SHARPLY DEFINED DRYLINE
EXTENDING NNEWD FROM NW TX ACROSS WRN OK INTO SRN KS. NUMEROUS
THUNDERSTORMS ARE DEVELOPING ALONG AND JUST TO THE EAST OF THE
DRYLINE. THESE STORMS HAVE ACCESS TO STRONG INSTABILITY ACROSS MUCH
OF WRN OK WHERE MLCAPE IS ESTIMATED IN THE 2000 TO 3500 J/KG RANGE.
IN ADDITION...THE FREDERICK OK WSR-88D VWP SHOWS A GRADUALLY VEERING
WIND PROFILE WITH HEIGHT AND A NEARLY UNIDIRECTIONAL WIND PROFILE IN
THE LOWEST 2 KM. THIS SHOULD BE FAVORABLE FOR SPLITTING CELLS. THE
LATEST WRF-HRRR CONFIRMS THIS BY MOVING A COUPLE OF LIFT SPLIT
SUPERCELLS NNEWD INTO SCNTRL KS OVER THE NEXT FEW HOURS. THE STRONG
INSTABILITY IS CONTRIBUTING TO STEEP MID-LEVEL LAPSE RATES OF 8.0 TO
8.5 C/KM WHICH WILL BE FAVORABLE FOR LARGE HAIL WITH THE MORE
INTENSE UPDRAFTS. ALSO...LARGE SFC TEMP-DEWPOINT SPREADS OF 25 TO 35
DEGREES SHOULD HELP ACCELERATE DOWNDRAFT SPEEDS MAKING WIND DAMAGE A
POSSIBILITY AS WELL.

..BROYLES/THOMPSON.. 05/07/2014

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...TOP...ICT...OUN...DDC...

LAT...LON   34729882 35459765 36829704 38189638 38649675 38599785
            37589870 35879947 35169960 34729882

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 7, 12:59 PM CDTMesoscale DiscussionSPCCheyenne2 hr
May 7, 1:37 PM CDTSevere Thunderstorm WatchSPCCheyenne, Decatur, Rawlins7 hr
May 7, 5:05 PM CDTMesoscale DiscussionSPCCheyenne, Rawlins85 min
May 7, 5:10 PM CDTSevere Thunderstorm WatchSPCBarton, Butler, Ellsworth, Harper, Harvey, Kingman and 8 more6 hr
May 7, 6:17 PM CDTSevere Thunderstorm WatchSPCClay, Dickinson, Geary, Marshall, Morris, Nemaha and 4 more5 hr
May 7, 1:54 PM CDTMesoscale DiscussionSPCCaddo, Comanche, Cotton, Grady, Jackson, Kiowa and 3 more66 min
May 7, 2:18 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Comanche and 17 more8 hr
May 7, 6:26 PM CDTMesoscale DiscussionSPCCanadian, Carter, Cleveland, Cotton, Garfield, Garvin and 15 more64 min

Nearby

Mesoscale Discussions in Oklahoma, 2014Mesoscale Discussions in Kansas, 2014Every mesoscale discussion in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.